The field of the invention is integrated circuit packaging.
As the amount of power required by ICs increases, there is increasing difficulty in passing sufficient power through interconnects to the ICs. To make the issue worse, as the IC power has risen, the voltages have dropped from 5 V to 3.3 V, then to 1.2 V, and now approach 1V. This increase in power and decrease in voltage has caused the current required to increase rapidly. At the same time the number of I/O""s and the switching rates are increasing while the I/O pitch on the chip is decreasing. All of this causes high dI/dt power noise which make clean power distribution difficult. Although the use of decoupling capacitors can help reduce such noise, building capacitors into a substrate filled with high density visa tends to be difficult and costly.
The present invention is directed to utilizing the xe2x80x9cdead spacexe2x80x9d previously occupied by a metal stiffener in an integrated circuit package as a location for power conditioning and converting mechanisms such as de-coupling capacitors and planar transformers.
Various objects, features, aspects and advantages of the present invention will become more apparent from the following detailed description of preferred embodiments of the invention, along with the accompanying drawings in which like numerals represent like components.